package Utiles;

//
// ExtensionFileFilter.java
//

/*
VisAD system for interactive analysis and visualization of numerical
data.  Copyright (C) 1996 - 2001 Bill Hibbard, Curtis Rueden, Tom
Rink, Dave Glowacki, Steve Emmerson, Tom Whittaker, Don Murray, and
Tommy Jasmin.
 
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
 
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.
 
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA
 */

import java.io.File;
import javax.swing.filechooser.FileFilter;

/** A file filter based on file extensions, for use with a JFileChooser. */
public class ExtensionFileFilter extends FileFilter {
    
    /** list of valid extensions */
    private String[] exts;
    
    /** description */
    private String desc;
    
    /** construct a new filter that accepts the given filter */
    public ExtensionFileFilter(String extension, String description) {
        this(new String[] {extension}, description);
    }
    
    /** construct a new filter that accepts the given filters */
    public ExtensionFileFilter(String[] extensions, String description) {
        exts = new String[extensions.length];
        System.arraycopy(extensions, 0, exts, 0, extensions.length);
        desc = description + " (*." + exts[0];
        for (int i=1; i<exts.length; i++) desc = desc + ", *." + exts[i];
        desc = desc + ")";
    }
    
    /** accept files with the proper extentions */
    public boolean accept(File f) {
        if (f.isDirectory()) return true;
        
        String name = f.getName();
        int index = name.lastIndexOf('.');
        String ext = index < 0 ? "" : name.substring(index + 1);
        
        for (int i=0; i<exts.length; i++) {
            if (ext.equalsIgnoreCase(exts[i])) return true;
        }
        
        return false;
    }
    
    /** return the filter's description */
    public String getDescription() {
        return desc;
    }
}
